Blowby under load?

[tjm]

When I had my Randys transmission installed the installer noted that there was oil leaking from the turbo. I had experienced this before when the drain tube didn't have the correct angles to it. I cleaned it up and proceeded to break in my transmission, every so often checking to see if the turbo was leaking. Normal city and highway driving it does not leak. I went to pick up 2000 lbs of horse feed - checked the turbo after that trip - no leaking. Hauled 13K lbs of alfalfa cubes and found this when i got home. You can see its slinging around the turbo. Oil fill is correct. The oil fill cap sits on top of the oil fill hole loosely and doesn't dance around when idling. The breather is 20K miles old - I removed and inspected, looks fine. I checked the air filter (Mopar) it was dirty, so i replaced it (13K miles on it). The air indicator gauge was all green - in fact I'm wondering if thats workin at all anymore.

108K miles on the vehicle with some heavy towing (reason i have a new transmission)

This video gives a real good explanation on why a turbo leaks



any ideas on what to check? Will an autoengenuity tool help diagnose? Any help much appreciated.

 

[Signal73]

Probably leaking boost into the center section. May be time for a rebuild.

 

[tjm]

Probably leaking boost into the center section. May be time for a rebuild.

and the only way to tell is a compression test?

 

[Darkbloodmon]

and the only way to tell is a compression test?

If you want to be that definitive then yes. Replacing a turbo on these trucks is alot more straightforward than pulling each injector for a test to make an accurate call.

 

[Signal73]

How’s the shaft movement, any in or out at all? Or any up and down play that will allow the wheel to contact the housing?

 

[tjm]

How’s the shaft movement, any in or out at all? Or any up and down play that will allow the wheel to contact the housing?

I had the turbo re-built about 2 years ago - i was causing a leak due to me mishandling the drain tube when i installed a new exhaust manifold. So i took it to get rebuilt and still had the leak which led me to straighten out the drain tube. I'll add this on my things to check for this problem.

I'm probably going to load up my trailer with my tractor and go for a ride to see if I can repeat the issue. I could have sworn I was loosing power in 1st when hauling that 13K load - it just seemed to not want to pull as much - it could of course be all. in my head as well as Im no expert.

@Darkbloodmon your basically saying the same thing - check the turbo before a compression test cuz its easier.

 

[Ozymandias]

Do you have oil in the compressor outlet towards the intercooler?

 

[tjm]

Do you have oil in the compressor outlet towards the intercooler?

Yes there is a bit of oil all the way up to the air intake

 

[BigPapa]

Yes there is a bit of oil all the way up to the air intake

Then, you don’t need to drive it or even run it. Way too much chance of a runaway.

 

[tjm]

Oil in your turbo?

1. Improper drain
2. excessive crankcase pressure
3. Dirty air filter
4. too much forward and back shaft play.

I can rule out 1. I will check for 4 tonight. I put in a new air filter - Mopar so I can rule out 3 now

checking for shaft play

 

[tjm]

No back and forth turbo shaft play.

 

[tjm]

Well I think I can rule out excessive crankcase pressure. See here

Ina couple of months I'll be picking up some more alfalfa for the horses, so a 13K lb load and see if there is any oil leakage. Will report back.

 

[tjm]

ok picked up ~2500 lbs of feed, in the bed, drove 45 miles @ 75mph. have oil coming up from the turbo drain again.

I had previously performed a blow by test here : https://www.turbodieselregister.com/threads/blowby-manometer.275445/
if you believe the test i don't have a blow by problem. That test tested the pressure from the oil fill tube, so the bottom of the oil pan.
No turbo shaft play, new air filter.

I have 2 theories :

1. The turbo drain tube doesnt have the right bend in it and crankcase pressure under load is blowing straight up the drain tube into the bottom of the turbo.

2. I ran a cylinder contribution test, engine at operating speed, pulled over and took this measurement. Could cylinder 3 rings be shot? causing extra pressure under load?

1: 102%
5: 100%
3: 93%
6: 99%
2: 102%
4: 103%

Pic of turbo drain tube from genos - wondering if the bend is intentional as to stop blow by - up.


My tube "bend"

Oil



Anyone have any ideas?

 

[Tuesdak]

ok picked up ~2500 lbs of feed, in the bed, drove 45 miles @ 75mph. have oil coming up from the turbo drain again.

Anyone have any ideas?

Watch some youtube of "Diesel Engine Runaway" and make sure you have a plan to drop the shifter into "N" if this happens. @BigPapa didn't make this risk about "PARK IT Till it's fixed" clear to you: your engine may be about to snort enough of it's own oil to run away till it comes apart as shrapnel. If you have oil pooled up in the intercooler romping it getting the boost up can suddenly blow it out into the engine and you have a runaway!

You have oil all the way to the air filter in the intake? This isn't clear. This is a critical decision point in diagnosis seeing if it's blowby from the crankcase or just oil leaking at the compressor side seal of the turbo.

I will assume there is oil on the suction side of the turbo. The only place that can come from is the crankcase breather. You may "Road Draft Tube" it plugging the intake hole for testing. Of note I suggest inspecting the breather and drain.

I would remove and drain the intercooler in case it does have oil in it ready to cause you problems.

I would send an oil sample out in case your oil is thin, fuel diluted, etc.

Verify the oil level isn't overfilled.

I do agree the turbo drain could be the problem as there are stories out there of engine runaway when idling at a steep angle where the turbo drain at the oil pan becomes submerged in oil.

1. The turbo drain tube doesnt have the right bend in it and crankcase pressure under load is blowing straight up the drain tube into the bottom of the turbo.

Full Stop! Nothing is blowing back up the drain tube.

Just covering the drain tube say with the oil level in the oil pan from a steep angle, overfilled, etc. causes problems. Because the turbo isn't just returning oil. It's returning oil and any "air" that leaks by the compressor shaft seals.

A bad bend in the drain tube that could pool oil like a drain trap could cause you problems. IMO I don't see this in your pictures of the drain tube. But not so good pictures and you are maybe seeing something that I am not there to also see.

I will assume from your blowby test that the intake is "dry" (no oil in it) from the air filter to the turbo inlet. Other than damp from the crankcase vent.

Drain tube and oil level... Than who rebuilt the turbo? How long is the warranty?

 

[Grumpy8811]

ok picked up ~2500 lbs of feed, in the bed, drove 45 miles @ 75mph. have oil coming up from the turbo drain again.

I had previously performed a blow by test here : https://www.turbodieselregister.com/threads/blowby-manometer.275445/
if you believe the test i don't have a blow by problem. That test tested the pressure from the oil fill tube, so the bottom of the oil pan.
No turbo shaft play, new air filter.

I have 2 theories :

1. The turbo drain tube doesnt have the right bend in it and crankcase pressure under load is blowing straight up the drain tube into the bottom of the turbo.

2. I ran a cylinder contribution test, engine at operating speed, pulled over and took this measurement. Could cylinder 3 rings be shot? causing extra pressure under load?

1: 102%
5: 100%
3: 93%
6: 99%
2: 102%
4: 103%


Anyone have any ideas?

as far as as question 1 goes, its just a gravity feed drain pipe back to the sump, so unless it is kinked to the point oil won't drain that probably isn't a contributor.

as far as question#2 goes, it could be the injectors too... but its a difficult thing to just pinpoint one thing without more testing because it could be a leaking valve or a weaker cylinder ring seal or both... . I don't know if there is a way to do a cylinder leakdown test on these engines or not but a cylinder leakdown test would narrow it down farther than a cylinder contribution test..

my guess is the turbo seals are leaking and that is all it is..

as far as runaway engines from oil blowing past the turbo seals, while that is a possibility it takes a heckuva lot of oil for that to happen. I experienced it one time in my work life while doing road service, had a roadcall where they said the vehicle was on fire.. and what it as was running away on lube oil going past the turbo. I could see the smoke cloud from 2 miles away it was smoking that much, but they time I got there it had been doing this for probably 30 minutes... I broke the fuel line off the fuel filter with a hammer which didn't phase it,,, and then I realized what was going on... and I shot a 10 lbs fire extinguisher into the intake which did the job.. but reality was it was too late...

 

[tjm]

Thanks for the response @Tuesdak, @Grumpy8811. I'm aware of the runaway potential. I always have a towel in the car that i can use to stuff into the air intake.
Turbo was from 3 years ago. I did check the shaft play its not moving back and forth. Up and down a bit like its supposed to.

I'll do some more sleuthing this weekend

 

[Tuesdak]

I always have a towel in the car that i can use to stuff into the air intake.

Bad plan. You will watch the towel get sucked into the intake like it's a Shop-Vac. Then the turbo may grenade from the towel debris while you watch what's left of towel chunks exit the exhaust on fire.

The fire extinguisher dumped into the intake is one plan. Otherwise you need something solid to stop 14PSI of atmospheric pressure trying to get in. Thin phone books have come out the exhaust as confetti in some cases.

The safest place to stand is in front or behind a runaway engine. When it stops, if it doesn't come apart, the cooling system may explode say by launching the radiator cap or top of the radiator off. Funny to watch the end of a video when they start walking toward a runaway after it stopped and they are running for their lives after "Boom!" the radiator cap goes straight up propelled by the contents of an overheated cooling system.

Yeah risk of shrapnel injury and burns from hot oily parts or coolant if something comes apart while you're trying to stop it.

@Grumpy8811 Consider a moment how little fuel a diesel engine uses at idle to no-load full RPM. It doesn't take much to give a diesel enough fuel in the intake to run away. Too much starting fluid, Natural Gas, Propane vapors, excessive blowby, bad turbo seal... The Deepwater Horizon turned into a disaster when one of their generators snorted gas and the engine air shutoff failed to operate. When the engine blew up the gas vapors exploded.

 

[Grumpy8811]

shoot I had a red shop towel in my pocket while working on a Detroit Series 50 with the intake piping removed and the engine sucked the rag right out of my pocket and went right thru the engine and out the exhaust.. I wouldn't depend on a rag for that. I was not expecting that.

I worked with 2 guys who were both missing parts of their fingers because they got to close to the turbo on a running engine and it sucked their finger in.. they ignored using a a grate designed to cover the turbo and paid the price. One of them was my best buddy, he said afterwards he didn't even feel it.. until he saw he was bleeding.. I know it isn't something to play with.. long story short, it ate up his knuckle on his middle finger, the docs told him it would heal but the finger would never bend again so he chose for them to amputate it..

that said it has to be a fairly big oil leak getting atomized in the turbo and sprayed into the intake for it to want to run on motor oil so you have a chance to get turbo fixed as seeing a bit of oil in the turbo is not that rare of a thing but it is an indication you need to fix it sooner rather than later.

 

[tjm]

Oil level right in the middle of the safe zone.
crankcase breather filter has 20K miles on it - i did pull it out of the crankcase and disconnect the larger of the two tubes when i started this thread. no oil in the breather and no obstructions in the larger tube - Ill re-check, including the smaller this time.
Ill send the oil for analysis as well, as soon as i find a place.
Air intake tube to the turbo is dry.
Here is a pic of the turbo inlet.

 

[Tuesdak]

I see oil in front of the compressor in that pic. If the tube you just took off is dry than turbo time.